The SICK KTX-WP91142252 is a contrast sensor built to spot mark-to-background differences on fast-moving webs or labels. It uses an RGB LED light source — red, green, and blue — so it locks onto the color contrast, not just the brightness. That 10 µs response time means it can catch a registration mark at line speeds that would blur a slower photoelectric. Sensing range is fixed at 13 mm, which puts the sensor close to the target but well within the reach of a standard mounting bracket on a packaging machine.
The 13 mm sensing distance is short — this isn't a prox sensor you stand back from. You mount it tight to the web, typically 10–13 mm off the surface. The RGB LED handles tricky contrasts like a white-on-white label or a colored mark on a similar-colored background; a fixed-red sensor might miss those. The PNP output (100 mA load) is standard for most PLC inputs, and the Light-ON / Dark-ON switch lets you pick whether the output fires on the mark or the gap. IP67 means it handles washdowns on a packaging line — no extra enclosure needed.
The housing is 30 mm wide, 53 mm tall, 78.5 mm deep — a compact block that fits on a standard 30 mm bracket or a 20 mm rod mount with the right clamp. Termination is an M12 5-pin male connector; the mating cable (not included) needs to be ordered separately. Pinout is standard for SICK sensors: brown (L+), blue (L-), black (output), white (Light-ON / Dark-ON select), and gray (not used on this variant). Operating voltage is 11–24 VDC; keep the supply clean — inductive kick from a nearby contactor can glitch the sensor if you don't use a snubber.